diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index dfc5993931..fc4036f931 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -377,6 +377,75 @@ jobs:
         echo "Running it..."
         ls
 
+  ubuntu-clang-sanitize-undefined:
+    runs-on: ubuntu-latest
+    timeout-minutes: 30
+    env:
+      VFLAGS: -cc clang
+    steps:
+    - uses: actions/checkout@v2
+    - uses: actions/setup-node@v1
+      with:
+        node-version: 12.x
+    - name: Install dependencies
+      run: |
+         sudo rm -f /etc/apt/sources.list.d/dotnetdev.list /etc/apt/sources.list.d/microsoft-prod.list;
+         sudo apt-get update;
+         sudo apt-get install --quiet -y postgresql libpq-dev libssl-dev sqlite3 libsqlite3-dev valgrind
+         sudo apt-get install --quiet -y libglfw3 libglfw3-dev  libfreetype6-dev  libxi-dev libxcursor-dev libasound2-dev
+         sudo apt-get install clang
+         ## sudo apt-get install --quiet -y libsdl2-dev libsdl2-ttf-dev libsdl2-mixer-dev libsdl2-image-dev
+    - name: Build V
+      run: make -j4 && ./v -cc clang -cg -cflags -Werror -o v cmd/v
+    - name: Fixed tests (-fsanitize=undefined)
+      run: ./v -cflags -fsanitize=undefined test-fixed
+    
+  ubuntu-clang-sanitize-address:
+    runs-on: ubuntu-latest
+    timeout-minutes: 30
+    env:
+      VFLAGS: -cc clang
+    steps:
+    - uses: actions/checkout@v2
+    - uses: actions/setup-node@v1
+      with:
+        node-version: 12.x
+    - name: Install dependencies
+      run: |
+         sudo rm -f /etc/apt/sources.list.d/dotnetdev.list /etc/apt/sources.list.d/microsoft-prod.list;
+         sudo apt-get update;
+         sudo apt-get install --quiet -y postgresql libpq-dev libssl-dev sqlite3 libsqlite3-dev valgrind
+         sudo apt-get install --quiet -y libglfw3 libglfw3-dev  libfreetype6-dev  libxi-dev libxcursor-dev libasound2-dev
+         sudo apt-get install clang
+         ## sudo apt-get install --quiet -y libsdl2-dev libsdl2-ttf-dev libsdl2-mixer-dev libsdl2-image-dev
+    - name: Build V
+      run: make -j4 && ./v -cc clang -cg -cflags -Werror -o v cmd/v
+    - name: Fixed tests (-fsanitize=address)
+      run: ASAN_OPTIONS=detect_leaks=0 ./v -cflags -fsanitize=address test-fixed
+
+  ubuntu-clang-sanitize-memory:
+    runs-on: ubuntu-latest
+    timeout-minutes: 30
+    env:
+      VFLAGS: -cc clang
+    steps:
+    - uses: actions/checkout@v2
+    - uses: actions/setup-node@v1
+      with:
+        node-version: 12.x
+    - name: Install dependencies
+      run: |
+         sudo rm -f /etc/apt/sources.list.d/dotnetdev.list /etc/apt/sources.list.d/microsoft-prod.list;
+         sudo apt-get update;
+         sudo apt-get install --quiet -y postgresql libpq-dev libssl-dev sqlite3 libsqlite3-dev valgrind
+         sudo apt-get install --quiet -y libglfw3 libglfw3-dev  libfreetype6-dev  libxi-dev libxcursor-dev libasound2-dev
+         sudo apt-get install clang
+         ## sudo apt-get install --quiet -y libsdl2-dev libsdl2-ttf-dev libsdl2-mixer-dev libsdl2-image-dev
+    - name: Build V
+      run: make -j4 && ./v -cc clang -cg -cflags -Werror -o v cmd/v
+    - name: Fixed tests (-fsanitize=memory)
+      run: ./v -cflags -fsanitize=memory test-fixed
+
 #  ubuntu-autofree-selfcompile:
 #    runs-on: ubuntu-18.04
 #    timeout-minutes: 30
diff --git a/cmd/tools/vtest-fixed.v b/cmd/tools/vtest-fixed.v
index 9a93cf8d77..a569e19dc6 100644
--- a/cmd/tools/vtest-fixed.v
+++ b/cmd/tools/vtest-fixed.v
@@ -5,6 +5,55 @@ import testing
 import v.pref
 
 const (
+	skip_with_fsanitize_memory  = [
+		'vlib/x/websocket/websocket_test.v',
+		'vlib/encoding/csv/reader_test.v',
+		'vlib/net/tcp_test.v',
+		'vlib/net/tcp_simple_client_server_test.v',
+		'vlib/net/udp_test.v',
+		'vlib/net/http/cookie_test.v',
+		'vlib/net/http/http_test.v',
+		'vlib/net/http/status_test.v',
+		'vlib/orm/orm_test.v',
+		'vlib/sqlite/sqlite_test.v',
+		'vlib/vweb/tests/vweb_test.v',
+		'vlib/x/websocket/websocket_test.v',
+		'vlib/v/tests/unsafe_test.v'
+	]
+	skip_with_fsanitize_address  = [
+		'vlib/encoding/base64/base64_test.v',
+		'vlib/encoding/csv/reader_test.v',
+		'vlib/flag/flag_test.v',
+		'vlib/io/util/util_test.v',
+		'vlib/io/reader_test.v',
+		'vlib/json/json_test.v',
+		'vlib/net/http/cookie_test.v',
+		'vlib/os/inode_test.v',
+		'vlib/os/os_test.v',
+		'vlib/regex/regex_test.v',
+		'vlib/semver/semver_test.v',
+		'vlib/sync/channel_opt_propagate_test.v',
+		'vlib/time/parse_test.v',
+		'vlib/v/fmt/fmt_keep_test.v',
+		'vlib/v/fmt/fmt_test.v',
+		'vlib/v/tests/array_init_test.v',
+		'vlib/v/doc/doc_test.v',
+		'vlib/v/tests/const_test.v',
+		'vlib/v/tests/fn_multiple_returns_test.v',
+		'vlib/v/tests/inout/compiler_test.v',
+		'vlib/v/tests/option_default_values_test.v',
+		'vlib/v/tests/option_test.v',
+		'vlib/v/tests/ptr_arithmetic_test.v',
+		'vlib/v/tests/str_gen_test.v',
+		'vlib/v/tests/unsafe_test.v',
+		'vlib/v/tests/vmod_parser_test.v',
+		'vlib/v/vcache/vcache_test.v',
+		'vlib/x/json2/decoder_test.v',
+		'vlib/x/websocket/websocket_test.v'
+	]
+	skip_with_fsanitize_undefined  = [
+		'vlib/encoding/csv/reader_test.v'
+	]
 	skip_test_files     = [
 		'vlib/net/http/http_httpbin_test.v',
 	]
@@ -53,6 +102,29 @@ fn main() {
 	mut tsession := testing.new_test_session(cmd_prefix)
 	tsession.files << all_test_files
 	tsession.skip_files << skip_test_files
+	mut sanitize_memory := false
+	mut sanitize_address := false
+	mut sanitize_undefined := false
+	for arg in args {
+		if '-fsanitize=memory' in arg {
+			sanitize_memory = true
+		}
+		if '-fsanitize=address' in arg {
+			sanitize_address = true
+		}
+		if '-fsanitize=undefined' in arg {
+			sanitize_address = true
+		}
+	}
+	if sanitize_memory {
+		tsession.skip_files << skip_with_fsanitize_memory
+	}
+	if sanitize_address {
+		tsession.skip_files << skip_with_fsanitize_address
+	}
+	if sanitize_undefined {
+		tsession.skip_files << skip_with_fsanitize_undefined
+	}
 	//
 	if os.getenv('V_CI_MUSL').len > 0 {
 		tsession.skip_files << skip_on_musl